The present disclosure relates to toilet flush valves configured to impart multiple flush types (e.g. dual flush) from a toilet tank into a toilet bowl. For purposes of discussion, a toilet tank typically has a flush valve assembly that is forced opened and remains opened until a predetermined volume of liquid flows from the tank into the toilet bowl through the flush valve assembly. Liquid is supplied to the toilet tank through a fill valve from a liquid supply line to the toilet tank. In practice, the fill valve opens when the fluid level in the tank falls below a predetermined liquid level.
Flush valve assemblies typically include a flush valve, a float and an actuation mechanism. The actuation mechanism causes the flush valve to open and release liquids stored in the tank into the toilet bowl and close when the float reaches a predetermined liquid level in the tank. For a dual flush valve, the toilet bowl may be refilled with liquids during the time the fill valve fills the toilet tank. The predetermined volume of liquid that refills the toilet bowl is sufficient to seal off the trap way of the bowl. In practice this predetermined volume amount may be defined as ratio of the total liquid volume supplied by the fill valve during a particular flush cycle. The fill valve feeds the liquids and feeds them to the tank bowl.
Toilets that can impart dual flushes have been found to be particularly advantageous in several situations. Specifically, prior to initiating a flush, a user may choose between a large flush water volume for solid waste (e.g. a full flush) or a smaller flush water volume for liquid waste (e.g. a partial flush). This may be done via a switch, button or the like on the actuation mechanism.
In general, dual flush valves (shown in FIG. 2) may be equipped with a flush volume controlling device associated with a flush volume, a drain opening lock, and full and partial flush control devices in order to maximize the volume of respective full and partial flushes. Full and partial flush control devices are typically adjustable to maximize respective flush volumes. Typically, a dual flush canister valve typically has a bottom reservoir that holds or retains a flush float therein. Further, a pair of adjustable height floats may be provided with the dual flush canister valve. One float is associated with a full flush and the other float is associated with a half flush.
The actual volume of a flush corresponds to an adjustable height at which each of the respective floats are set (e.g. set by the manufacturer). OEM toilet manufacturers may preset the height of a respective float in order to comply with relevant code such as the U.S. Environmental Protection Agency's “Water Sense”. However, if the end-user is capable of altering or otherwise modifying the float height, this risks violating the relevant code since the resultant flush volume associated with a respective float. Further, being able to modify relevant float settings risks performance efficiency of a given flush valve assembly and thus waste of resources in the long run.
Accordingly, there is a need to resolve this problem so that end users are prevented from altering float settings.